This application claims the priority of Japanese Patent Application No. 6-79324 filed on Mar. 24, 1994.
1. Field of the Invention
The present invention relates to the structure of a film loading apparatus for winding a predetermined amount of film which is fed from a patrone around a take-up spool spool when the patrone is set in a camera.
2. Description of the Related Art
Autoloading apparatuses for automatically winding a predetermined amount of film which is fed from a patrone around a take-up roll when the patrone is set in a camera are now generally used. As an autoloading apparatus is known not only an apparatus for feeding film to a take-up spool by using a rotating member, but also an apparatus for feeding film to a take-up spool by the reciprocating movement of a feeding member having a claw, as disclosed in, for example, Japanese Patent Laid-Open No. 3-200947. This reciprocating movement system is advantageous in that members such as a gear train and the like which are necessary in the film feeding system using a rotating member are obviated, thereby obviating the space they occupy and, hence, enabling the reduction in the size of a camera as a whole.
FIGS. 6(A) and 6(B) show a conventional film loading apparatus of a reciprocating movement system. In FIGS. 6(A) and 6(B), a take-up spool in a camera is seen from the bottom portion of the camera. In these drawings, a spool 1 is provided with a plurality of catches 2, and a spool cam 4 having a projection 3 is attached to the bottom portion of the spool 1. A film feeding member 5 is provided with a claw 6 and a pin 7. The pin 7 slides along a guide groove 8. The feeding member 5 is also provided with a driving lever (not shown) which engages the spool cam 4, so that the feeding member 5 intermittently reciprocally moves along the guide groove 8 with the rotation of the spool cam 4. A film guide plate 10 having comparatively small elastic force is provided on the inner surface 9 of the back lid of the camera.
According to this structure, the feeding member 5 reciprocally moves with the rotation of the spool 1, and when the claw 6 engages one of the perforations 12 of the film 11 at the time of forward movement of the feeding member 5, the film 11 is fed toward the spool 1. When the catch 2 on the spool 1 engages the perforation 12, the film 11 is wound around the spool 1. In this manner the the film 11 is set in an initial state which allows photographing.
In such a film loading apparatus, however, sometimes a perforation at the forward end portion is inconveniently broken or enlarged (transformed). For example if the claw 6 enters another perforation 12 while the perforation 12 at the forward end portion of the film 11 is engaged with the catch 2 on the spool 1 during the backward movement of the the feeding member 5, the film 11 is pulled in the opposite direction to the feeding direction. As a result, force is applied to the perforation 12 which is engaged with the catch 2 on the spool 1, which may result in the breakage of the perforation 12. In this case, it is impossible to take up the film 11 by the spool 1. Even if the perforation 12 at the forward end of the film 11 is not broken, the force of pulling the film backward sometimes enlarges the perforation 12 which is engaged with the catch 2, so that the forward end of the film 11 is bent toward the outside of the spool 1. In other words, the film 11 detours, and it is loosely wound around the spool 1. If the loosely wound film 11 becomes too bulky, it is impossible to photograph a predetermined number of exposures.